In conventional stroller, when the frames of the stroller are collapsed, it is necessary to hold the handlebar with one hand and operate a latch mechanism provided at the frame with the other hand so as to make the front wheel frame and the back wheel frame pivotally rotate each other to reach a collapsed state.
However, when the user holds something or an infant in one hand and no other can help her/him, it is difficult for her/him to collapse the frames only with the other hand.